While it's true that women experience depression and anxiety at higher rates than men, this still doesn't explain the intense level of prescription disparity. Even with disorders that skew heavily male, like ADHD, women are more likely to be prescribed medication.

Dr. Edward Shorter, a psychiatrist and author of How Everyone Became Depressed, told VICE that "there is such a thing as a 'depressed role' that really does increase the differences between the sexes remarkably." And Pharmaceutical marketing like antidepressant commercials and magazine ads that disproportionately target sad young women play a part in perpetuating that role.

Direct-to-consumer advertising has an abundance of "dramatic images of women who were locked in the depths of despair," according to Shorter. "On the next page, you see them beaming with delight, hand wrestling in the bar after they take their antidepressant."

But this isn't unique to today's women. Females have long been targeted by pharmaceutical advertising, and massive disparities in prescription drug use have been around almost as long as prescription drugs.

"One of the functions of our medical system since it has organized itself has been to hand out stimulants and sedatives to American women," says David Herzberg, author of Happy Pills in America: From Miltown to Prozac.

One of the earliest painkillers, morphine, was a notoriously feminine vice. Though men also partook, it was mostly American women who became addicts in the 19th century, including the wife of our 16th president, Mary Todd Lincoln, who used an opiate called laudanum to treat, among other things, her nervousness.

Morphine and drugs like laudanum treated the distinctly female conditions of pregnancy, childbirth, and menstrual pain. They also had the added benefit of not being alcohol—a drug that 19th century American women crusaded against, and a transgression that could besmirch one's reputation. By the end of the 1800s, more than two thirds of the country's opium and morphine addicts were women.

Cocaine, chloroform, and cannabis were also employed in the late 19th century to treat a range of gynecological complaints, as well as neurasthenia, a vague nervous condition of Freudian origins that physicians of the era predominantly attributed to women. In 1901, the Boston Globe reported that "oxygen parties" saw upper class, white women inhaling the nitrous oxide prescribed to sedate them. At least one medical textbook from the time advised the use of marijuana over chloral or morphine to treat nervousness.

Beecham's ad circa 1800s. Image via Universal History rchive/Getty

By 1903, a new addictive class of pharmacological agents called barbiturates was on the rise. Used as sedatives meant to treat nervousness and anxiety, the drugs' common use as a sleeping pill fit nicely with the common "rest cure" prescribed to women (including Virginia Woolf and Charlotte Perkins Gilman) by era physicians. Like their opiate-laced predecessors, the pills were highly addictive.

But it wasn't until 1945 or so that the public realized just how addictive. The ensuing moral panic over a hooked America utilized the country's own anxieties over its women to churn out sensational stories warning against drugs' effects, especially on the weaker sex. "The sense was that these women were kind of 'innocents' who would never have wanted to experience a drug effect. They were 'just following doctors' orders,'" says Herzberg.

Scare stories about women abandoning their duties or deviating from societal norms, like motherhood, played heavily in the press. A 1945 illustration in American Druggist magazine portrayed a female addict turning to prostitution, in keeping with girl-gone-addict-gone-bad cautionary tales. Eight years later FDA chief George Larrick told a subcommittee on juvenile delinquency that, because of barbiturates' addictive hold, "[Women] no longer take interest in the home or children, get dirty and slovenly; steal money and sell furniture to get the drug." These scare tactics were just a new twist on the dangerous drug du jour, of course. The media had been drumming up the threat of drugs to women's innocence since the release of films like Morphia—the Death Drug (1914), The Secret Sin (1915), and The Girl Who Didn't Care (1916).

"A mother kind of abandoning her children and pursuing deviant sex acts with people from another social class or another race: that's the most sexy story of all, in a certain way. And that was attached to addiction long before there was attention to problems with prescription drugs," Herzberg says.

Luckily, Miltown was right around the corner to assuage the public's anxiety. The new drug dropped in 1950 and quickly became a blockbuster hit with a debut perfectly timed to treat the trendy anxiety brought about by shifting gender roles and a renewed emphasis on neurasthenia. Its release also coincided with a rise in popular interest in psychiatry.

"The idea of psychiatric help, understood in Freudian terms, became a hugely popular concern. Everyone thought they should be better adjusted at work and be more mentally healthy. Anxiety was a trendy disorder, "says Nicolas Rasmussen, author of On Speed: The Many Lives of Amphetamine.

As men returned home from World War II and women reentered the domestic realm, "mother's little helpers" like Valium and Librium enabled housewives to cope with the mundane tasks of their everyday lives. Though the drugs were originally marketed to both genders, it quickly became clear that an ongoing national masculinity crisis would not allow for manly men to pop pills prescribed for effeminate nerves. By the time the earliest studies on the drug class were conducted in the 1960s, women were being prescribed Valium twice as much as men.

As the Miltown class of drugs became known as solely "women's drugs" in the 1950s and 60s, the kind of far-reaching neuroses the drugs treated were considered feminine as well. Medical journals from the time period depict "viciously misogynist" cartoons of stereotypically anxious female patients with "vague complaints" and anxieties, says Herzberg. From textbooks published at the same time, "it's clear that there [was] an expectation that women are mentally weak and that they're liable to have all kinds of neuroticism and anxiety," Herzberg added.

SSRIs are used by at least 25 percent of American women between ages 40-50.

Though modern women don't have to contend with the same kind of ignorance, there is still a common perception that the female sex is sadder, or at least more "emotional," than the opposite sex.

"People talk about how down they feel, how tired they feel, how depressed they feel; that kind of speech is commoner among women than it is among men," says Dr. Shorter.

Back in the 60s, feminists like Betty Friedan railed against the pharmaceutical industry's generalization of the "problem that has no name"—her label for the kind of fatigue and feelings of emptiness that many housewives were treating with popular tranquilizers—arguing that women's predisposition to nervous illness had less to do with anxiety and depression than their failure to live fulfilled lives. Herzberg agrees: "If you have a group of people whose life choices you're limiting, they're going to end up less happy, on average."

Today, psychiatrists like Julie Holland, author of Moody Bitch, argue that Big Pharma's barrage of marketing on daytime television and in women's magazines is creating a "new normal" in which understandable and biologically natural female emotion is overly medicated.

Which brings us to today's antidepressants and anti-anxiety medication: SSRIs are used by at least 25 percent of American women between ages 40-50. The national average stands at around 10%, with 1 in 10 Americans on antidepressants. With the arrival of Prozac in the late 1980s, selective serotonin re-uptake inhibitors like Zoloft and Paxil have enjoyed a relatively unchallenged reign as the leading blockbuster drugs for the past two decades. Part of the reason for the drugs' uninhibited success is the lack of harmful side effects like those seen in Valium, barbiturates, and morphine.

"They were pumped up greatly in the 90s. They're considered so safe that you might as well try it," says Rasmussen.

As the drugs went off patent in the 00s, Big Pharma now stands to gain less and SSRIs have lagged in popularity. The next frontier looks to be antipsychotic drugs of the class usually used to treat psychosis or bipolar disorder. Abilify, for example, is currently the number one selling drug in America, outperforming even nonpsychiatric drugs.

Just don't expect it to stay that way forever. "The whole gig, the whole blockbuster status relies on the magic of 'this will make everything better,'" says Herzberg.

And when that magic fades—as it's been shown to, time and time again—it's on to the next big thing.